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Characteristics of soil organic carbon andtotal nitrogen storages for differentland-use types in Central Yunnan Plateau 被引量:1
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作者 SHEN Fangyuan TUO Yunfei +4 位作者 WANG Qian WANG Fei ZHENG Yang DU Wenjuan XIANG Ping 《排灌机械工程学报》 CSCD 北大核心 2022年第5期519-528,共10页
Two-factor analysis of variance and redundancy analysis were used to analyze the characte-ristics of soil organic carbon total nitrogen storage in garden land,forestland,grassland,farmland,and bare land in the Dachunh... Two-factor analysis of variance and redundancy analysis were used to analyze the characte-ristics of soil organic carbon total nitrogen storage in garden land,forestland,grassland,farmland,and bare land in the Dachunhe watershed of Jinning District,Kunming City,Yunnan Province,China.The effects of the soil organic carbon,total nitrogen stratification ratio,soil physical and chemical factors on the storage characteristics of organic carbon and total nitrogen of different land-use types were analyzed.The results show that the rates of carbon and nitrogen stratification in soil from 0-20 cm and 40-60 cm of the same land-use types differed are statistically significant(P<0.05).The organic carbon and total nitrogen stratification ratio SR1 of garden land soil are 38.5%and 25.3%,respectively,which are higher than SR^(2).The soil organic carbon and total nitrogen stratification ratio SR^(2) of different land-use types are greater than SR1.There are statistically significant differences in the SR^(2) soil organic carbon and total nitrogen stratification ratios(P<0.05).Soil organic carbon and total nitrogen storage of diffe-rent land-use types gradually decrease with increasing soil depth,with the maximum soil organic carbon and total nitrogen storage in the 0-20 cm soil layer.Soil organic carbon and total nitrogen sto-rage at the same soil depth are significantly different(P<0.05).Soil organic carbon and total nitrogen storage in the garden land are greater than those in the other land-use types.Soil organic carbon and total nitrogen storage in 0-20 cm garden land are 4.96 and 3.19 times than those in bare land,respectively;soil organic carbon and total nitrogen storage are explained by 93.66%and 1.53%in redundancy analysis RDA1 and RDA2,respectively.All physicochemical factors except Available Phosphorus and pH are statistically significance with carbon and nitrogen storage(P<0.05).Soil cationic exchange capacity,Available Phosphorus,C/N ratio,and Moisture Content are positively correlated with organic carbon and total nitrogen storage.In contrast,soil Bulk Density is negatively correlated with organic carbon storage and total nitrogen storage.Available Phosphorus,C/N ratio,and Moisture Content are the main factors promoting soil organic carbon and total nitrogen accumulation. 展开更多
关键词 soil organic carbon storage soil total nitrogen storage stratification ratio land-use types Central Yunnan Plateau
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Soil Nutrients in Intensive Agricultural Areas with Different Land-Use Types in Qingzhou County, China 被引量:9
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作者 ZHAO Geng-Xing LI Xiu- Juan +2 位作者 WANG Ri-Yan LI Tao YUE Yu-De 《Pedosphere》 SCIE CAS CSCD 2007年第2期165-171,共7页
On the basis of the data obtained from a field survey, the relationship between land use and soil nutrients was evaluated in Qingzhou County, Shandong Province, China, through a statistical analysis of differences in ... On the basis of the data obtained from a field survey, the relationship between land use and soil nutrients was evaluated in Qingzhou County, Shandong Province, China, through a statistical analysis of differences in 17 nutrients in five types of cultivated land. The results showed significant effects (P < 0.05 or P < 0.01) of land-use type on soil organic matter and concentration of macronutrients, secondary nutrients, and micronutrients, as well as total salt and soil pH. In vegetable land, because of the large amounts of fertilizer applied to vegetable crops, the concentrations of most soil nutrients, with exception of available Si and micronutrients, were higher than those in grain cropland. Grain cropland had a significantly lower total salt content (P < 0.01) and tended to have a higher soil pH than vegetable land. Within subtypes of land use, dry land, irrigable land, and open-air vegetable land had the highest coefficient of variation (CV) for available P, whereas protected vegetable land had the highest CV for total N and available S. In general, land-use types had greater impact on macronutrients than on secondary nutrients and micronutrients. 展开更多
关键词 cultivated land land-use type Qingzhou County soil nutrients
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The effects of land-use types and conversions on desertification in Mu Us Sandy Land of China 被引量:5
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作者 HAO Chengyuan WU Shaohong 《Journal of Geographical Sciences》 SCIE CSCD 2006年第1期57-68,共12页
Based on multi-temporal remotely sensed materials of both 1985 and 2000, we analyzed the effects of land-use types and their conversions on desertification in Mu Us Sandy Land in the agro-pastoral transitional zone of... Based on multi-temporal remotely sensed materials of both 1985 and 2000, we analyzed the effects of land-use types and their conversions on desertification in Mu Us Sandy Land in the agro-pastoral transitional zone of north central China. In this study, the desertified land was classified into five degrees: potential, light, medium, severe and extreme. The results indicate that the extent of desertification expands slightly, while desertification degree is enhanced significantly. About 22.35% of the total land area in the study area is in the desertification course, and the expanded area of both severely and extremely desertified land accounts for 3.67% of the total area of Mu Us Sandy Land. About 9053 klTl2 of area witnessed changes in land-use types between 1985 and 2000, which accounted for 10.75% of the total. More importantly, the area of conversions among cultivated land, forestland and rangeland added up to 971.6 km^2. This research reveals that both improper land-use types and conversions could accelerate the desertification process. Both cultivated land and forestland have more effects on the desertification development than rangeland. Some land-use type conversions, such as rangeland to cultivated land, rangeland to forestland and forestland to cultivated land, are attributed to the acceleration of the desertification development while the opposite can control the desertification development. 展开更多
关键词 land-use type DESERTIFICATION Mu Us Sandy Land agricultural land agro-pastoral transitional zone
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Effects of land-use types on the vertical distribution of fractions of oxidizable organic carbon on the Loess Plateau, China 被引量:9
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作者 SUN Caili XUE Sha +2 位作者 CHAI Zongzheng ZHANG Chao LIU Guobin 《Journal of Arid Land》 SCIE CSCD 2016年第2期221-231,共11页
The oxidizability of soil organic carbon (SOC) influences soil quality and carbon sequestration. Four fractions of oxidizable organic carbon (very labile (C1), labile (C2), less labile (C3) and non-labile (C... The oxidizability of soil organic carbon (SOC) influences soil quality and carbon sequestration. Four fractions of oxidizable organic carbon (very labile (C1), labile (C2), less labile (C3) and non-labile (C4)) reflect the status and composition of SOC and have implications for the change and retention of SOC. Studies of the fractions of oxidizable organic carbon (OC) have been limited to shallow soil depths and agroecosystems. How these fractions respond at deep soil depths and in other types of land-use is not clear. In this study, we evaluated the vertical distributions of the fractions of oxidizable organic carbon to a soil depth of 5.0 m in 10 land-use types in the Zhifanggou Watershed on the Loess Plateau, China. Along the soil profile, C1 contents were highly variable in the natural grassland and shrubland I (Caragana microphylla), C2 and C4 contents were highly variable in the natural grassland and two terraced croplands, respectively, and C3 contents varied little. Among the land-use types, natural grassland had the highest C1 and C2 contents in the 0-0.4 m layers, followed by shrubland I in the 0-0.1 m layer. Natural grassland had the highest C4 contents in the 1.0-4.5 m layers. Natural grassland and shrubland I thus contributed to improve the oxidizability of SOC in shallow soil, and the deep soil of natural grassland has a large potential to sequester SOC on the Loess Plateau. 展开更多
关键词 Iand-use types deep soil oxidizable organic-carbon fractions Loess Plateau
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Variation of Zn content in soils under different land-use types in the Hetao oasis,Inner Mongolia of China
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作者 ZHU Yangchun ZHAO Xueyong +1 位作者 LIAN Jie CHEN Min 《Journal of Arid Land》 SCIE CSCD 2016年第6期861-870,共10页
Understanding the status and distribution of the micronutrient Zn in soils is important for managing plant growth and preventing soil pollution for agricultural irrigation systems in arid and semi-arid regions. In thi... Understanding the status and distribution of the micronutrient Zn in soils is important for managing plant growth and preventing soil pollution for agricultural irrigation systems in arid and semi-arid regions. In this study, a total of 195 soil samples from five soil layers (0-20, 20-40, 40-60, 60-80 and 80-100 cm) in the three land-use types (wasteland, forestland and cropland) after long-term agricultural fertilization and irrigation with Yellow River water were collected in the middle of the Hetao oasis, i.e. the Yongji irrigation sub-oasis. We analyzed the vertical and spatial distributions of Zn content and its relationship with soil properties to determine whether differences of Zn content existed in the soil profiles. The results revealed that the mean content of Zn was 107 mg/kg, 1.9 times higher than the background value (55.7 mg/kg) of the Hetao oasis and much lower than the secondary standard value (300 mg/kg) of the Chinese Environmental Quality Standard for Soils when pH〉7.5. Soil Zn contents were not significantly different and the coefficients of variation of Zn contents were less than 50% in the five soil layers. Soil Zn content was similar from southern to northern parts but increased from western to eastern parts in the sub-oasis. Soil Zn contents did not differ significantly among the three land-use types, but soil total nitrogen (TN) contents were significantly higher in the agriculturally managed forestland and cropland than in the wasteland (P〈0.05). Zn was significantly and positively correlated with TN (F=36.6, P〈0.001). The use of fertilizers may increase the content of Zn in soils, but flooding irrigation may minimize the differences in the spatial distribution of soil Zn content in the whole sub-oasis. This research is of important value for soil pollution control and sustainable land use management in arid and semi-arid regions. 展开更多
关键词 FERTILIZER land-use type spatial distribution soil profile soil property
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Study on Soil Infiltration Capability and Its Impact Factors of Different Land-use Types in Purple Soil Region
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作者 Bin MO Xiaoyan CHEN +7 位作者 Tao LIU Yicui YANG Zhixing LIN Xiufeng HUANG Qiliang HUANG Hui JIAN Tujin ZHOU Yunkang SHEN 《Asian Agricultural Research》 2016年第3期58-62,共5页
Soil infiltration capability is the hot spot topic of soil erosion studies and soil physical and chemical properties have great influence on it. A new infiltration method point- source infiltration method was used to ... Soil infiltration capability is the hot spot topic of soil erosion studies and soil physical and chemical properties have great influence on it. A new infiltration method point- source infiltration method was used to precisely evaluate the infiltration capability in different purple soil land- use types. And correlation analysis on soil physical and chemical properties and soil infiltration capability of different land- use types was performed. Results showed that:( i) there is a large difference among soil physical and chemical properties in different land- use types,soil water content,non- capillary porosity,capillary porosity,content of > 0. 25 mm aggregates and organic matter content in the top soil are greater than those in the subsoil;( ii) soil infiltration capability showed differences among different land- use types. Land use showed great effects,in general,the order of decrease on initial infiltration rate and average infiltration rate was: woodland slope > slope farmland >grassland,the order of decrease on steady infiltration rate was: slope farmland > woodland > grassland and the time reaching stable state was:slope farmland > woodland > grassland;( iii) correlation analysis showed that there was a significantly positive correlation between initial infiltration rate and wet sieve MWD value and structural damage rate,and it had a significantly negative correlation with capillary porosity;( iv)steady infiltration rate and non- capillary porosity showed the significantly positive correlation,and it had a significantly negative correlation with the soil bulk density;( v) the average infiltration rate and non- capillary porosity and structural damage rate showed a positive correlation and the correlation coefficient was large and there was a negative correlation between average infiltration rate and soil bulk density and capillary porosity,and the absolute value of correlation coefficient was relatively large. The results of this study can provide the theoretical basis for soil infiltration study in purple soil area. 展开更多
关键词 FORESTRY SOIL INFILTRATION CAPABILITY Point source INFILTRATION DIFFERENT land-use types SOIL physical and chemical properties Correlation
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Association between ABO Blood Types and the Risk of Gestational Diabetes Mellitus:A Prospective Cohort Study 被引量:1
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作者 Shuanghua Xie Shuangying Li +8 位作者 Shaofei Su Enjie Zhang Shen Gao Yue Zhang Jianhui Liu Minhui Hu Ruixia Liu Wentao Yue Chenghong Yin 《Biomedical and Environmental Sciences》 2025年第6期678-692,共15页
Objective To investigate the association between ABO blood types and gestational diabetes mellitus(GDM)risk.Methods A prospective birth cohort study was conducted.ABO blood types were determined using the slide method... Objective To investigate the association between ABO blood types and gestational diabetes mellitus(GDM)risk.Methods A prospective birth cohort study was conducted.ABO blood types were determined using the slide method.GDM diagnosis was based on a 75-g,2-h oral glucose tolerance test(OGTT)according to the criteria of the International Association of Diabetes and Pregnancy Study Groups.Logistic regression was applied to calculate the odds ratios(ORs)and 95%confidence intervals(CIs)between ABO blood types and GDM risk.Results A total of 30,740 pregnant women with a mean age of 31.81 years were enrolled in this study.The ABO blood types distribution was:type O(30.99%),type A(26.58%),type B(32.20%),and type AB(10.23%).GDM was identified in 14.44%of participants.Using blood type O as a reference,GDM risk was not significantly higher for types A(OR=1.05)or B(OR=1.04).However,women with type AB had a 19%increased risk of GDM(OR=1.19,95%CI=1.05–1.34;P<0.05),even after adjusting for various factors.This increased risk for type AB was consistent across subgroup and sensitivity analyses.Conclusion The ABO blood types may influence GDM risk,with type AB associated with a higher risk.Incorporating it—either as a single risk factor or in combination with other known factors—could help identify individuals at risk for GDM before or during early pregnancy. 展开更多
关键词 ABO blood type phenotype Cohort study Risk factors Gestational diabetes mellitus
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Retrospective analysis of pathological types and imaging features in pancreatic cancer: A comprehensive study
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作者 Yang-Gang Luo Mei Wu Hong-Guang Chen 《World Journal of Gastrointestinal Oncology》 SCIE 2025年第1期121-129,共9页
BACKGROUND Pancreatic cancer remains one of the most lethal malignancies worldwide,with a poor prognosis often attributed to late diagnosis.Understanding the correlation between pathological type and imaging features ... BACKGROUND Pancreatic cancer remains one of the most lethal malignancies worldwide,with a poor prognosis often attributed to late diagnosis.Understanding the correlation between pathological type and imaging features is crucial for early detection and appropriate treatment planning.AIM To retrospectively analyze the relationship between different pathological types of pancreatic cancer and their corresponding imaging features.METHODS We retrospectively analyzed the data of 500 patients diagnosed with pancreatic cancer between January 2010 and December 2020 at our institution.Pathological types were determined by histopathological examination of the surgical spe-cimens or biopsy samples.The imaging features were assessed using computed tomography,magnetic resonance imaging,and endoscopic ultrasound.Statistical analyses were performed to identify significant associations between pathological types and specific imaging characteristics.RESULTS There were 320(64%)cases of pancreatic ductal adenocarcinoma,75(15%)of intraductal papillary mucinous neoplasms,50(10%)of neuroendocrine tumors,and 55(11%)of other rare types.Distinct imaging features were identified in each pathological type.Pancreatic ductal adenocarcinoma typically presents as a hypodense mass with poorly defined borders on computed tomography,whereas intraductal papillary mucinous neoplasms present as characteristic cystic lesions with mural nodules.Neuroendocrine tumors often appear as hypervascular lesions in contrast-enhanced imaging.Statistical analysis revealed significant correlations between specific imaging features and pathological types(P<0.001).CONCLUSION This study demonstrated a strong association between the pathological types of pancreatic cancer and imaging features.These findings can enhance the accuracy of noninvasive diagnosis and guide personalized treatment approaches. 展开更多
关键词 Pancreatic cancer Pathological types Imaging features Retrospective analysis Diagnostic accuracy
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How to select favorable and promising alleles and genotypes for breeding:A case study of rice blast resistance genes in Southern and Northeastern China 被引量:1
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作者 Xing Wang Jinyan Wang +8 位作者 Yaling Zhang Yongxiang Yao Ying Sun Liping Lin Xuemei Ye Rongbai Li Zhibin Liang Yizhen Deng Qinghua Pan 《The Crop Journal》 2025年第1期104-114,共11页
Asian rice comprises two major subspecies:Xian(X)and Geng(G),and the diverged resistance genes(R)have provided a foundation for breeding improved cultivars to control rice blast disease.After conducting two-phase alle... Asian rice comprises two major subspecies:Xian(X)and Geng(G),and the diverged resistance genes(R)have provided a foundation for breeding improved cultivars to control rice blast disease.After conducting two-phase allele mining using six updated FNP marker systems,the functional haplotypes at Pit,Pib,and Pi63 strictly diverged into the X-populations and were defined as X-R loci,while those at Pi54,Pi37,and Pi36 into the G-populations as G-R loci.The genic diversity at the three X-R loci(16 alleles)was twofold higher than that at the three G-R loci(8 alleles),and the allelic diversity in the Southern region(21 alleles)was nearly double that in the Northeastern region(11 alleles).Both observations reflect a significant difference in genetic diversity between X-and G-populations,and indicate that the effective R-genes mainly originated from X-subspecies.Based on the allelic structures characterized by a set of 10 parameters,8 and 16 alleles were respectively recognized as favorable and promising ones for the regional breeding programs.The genotypic structures of the two regional populations were almost different,indicating that the diverged alleles have been further assembled into two series of regional genotypes through long-term breeding programs,despite the presence of one-third of region-common alleles.The genotypic diversity in the Southern region(55 genotypes)was nearly twice as high as that in the Northeastern region(28),which perfectly reflects the aforementioned differences in both genic and allelic diversities.After analyzing the genotypic structures using a set of 13 parameters,4 and 23 genotypes,respectively,can be recommended as the favorable and promising ones for the regional breeding programs.The case study serves as a concrete sample of how to identify the favorable and promising alleles and genotypes,and beneficial parents based their comprehensive population structures for gene-designed breeding. 展开更多
关键词 Rice blast Xian and Geng type resistance genes Allelic and genotypic population structures Favorable allele and genotype Promising allele and genotype
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Assessment of Chinese urban land-use efficiency(SDG11.3.1)utilizing high-precision urban built-up area data
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作者 Hao Wang Yafei Liu +2 位作者 Lianze Sun Xiaogang Ning Guangzhe Li 《Geography and Sustainability》 2025年第1期58-74,共17页
Assessment of SDG11.3.1 indicator of the United Nations Sustainable Development Goals(SDGs)is a valuable tool for policymakers in urban planning.This study aims to enhance the accuracy of the SDG11.3.1 evaluation and ... Assessment of SDG11.3.1 indicator of the United Nations Sustainable Development Goals(SDGs)is a valuable tool for policymakers in urban planning.This study aims to enhance the accuracy of the SDG11.3.1 evaluation and explore the impact of varying precision levels in urban built-up area on the indicator’s assessment outcomes.We developed an algorithm to generate accurate urban built-up area data products based on China’s Geographical Condition Monitoring data with a 2 m resolution.The study evaluates urban land-use efficiency in China from 2015 to 2020 across different geographical units using both the research product and data derived from other studies utilizing medium and low-resolution imagery.The results indicate:(1)A significant improvement in the accuracy of our urban built-up area data,with the SDG11.3.1 evaluation results demonstrating a more precise reflection of spatiotemporal characteristics.The indicator shows a positive correlation with the accuracy level of the built-up area data;(2)From 2015 to 2020,Chinese prefecture-level cities have undergone faster urbanization in terms of land expansion relative to population growth,leading to less optimal land resource utilization.Only in extra-large cities does urban population growth show a relatively balanced pattern.However,urban popula tion growth in other regions and cities of various sizes lags behind land urbanization.Notably,Northeast China and small to medium cities encounter significant challenges in urban population growth.The comprehensive framework developed for evaluating SDG11.3.1 with high-precision urban built-up area data can be adapted to different national regions,yielding more accurate SDG11.3.1 outcomes.Our urban area and built-up area data products provide crucial inputs for calculating at least four indicators related to SDG11. 展开更多
关键词 SDG11.3.1 land-use efficiency Urban built-up area URBANIZATION Population growth
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Evaluation and comparison of separated precipitation types from multisources data in the Chinese Tianshan mountainous region
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作者 YANG Chuanming LI Xuemei +2 位作者 ZHANG Xu WU Jun LI Lanhai 《Journal of Mountain Science》 2025年第2期489-504,共16页
Precipitation types primarily include rainfall,snowfall,and sleet,and the transformation of precipitation types has significant impacts on regional climate,ecosystems,and the land-atmosphere system.This study employs ... Precipitation types primarily include rainfall,snowfall,and sleet,and the transformation of precipitation types has significant impacts on regional climate,ecosystems,and the land-atmosphere system.This study employs the Ding method to separate precipitation types from three datasets(CMFD,ERA5_Land,and CN05.1).Using data from 26meteorological observation stations in the Chinese Tianshan Mountains Region(CTMR)of China as the validation dataset,the precipitation type separation accuracy of three datasets was evaluated.Additionally,the impacts of relative humidity,precipitation amount,and air temperature on the accuracy of precipitation type separation were analyzed.The results indicate that the CMFD dataset provides the highest separation accuracy,followed by CN05.1,with ERA5_Land showing the poorest performance.Spatial correlation analysis reveals that CMFD outperforms the other two datasets at both annual and monthly scales.Root Mean Square Error(RMSE)and Mean Deviation(MD)values suggest that CMFD is more consistent with the station observational data.The analysis further demonstrates that relative humidity and precipitation amount significantly affect separation accuracy.After bias correction,the correlation coefficients between CMFD,ERA5_Land,and station observational data improved to 0.85-0.94,while the RMSE was controlled within 2 mm.The study also revealed that the overestimation of precipitation was positively correlated with the overestimation of rainfall days,negatively correlated with the overestimation of snowfall days,and that underestimated air temperatures led to an increase in the misclassification of snowfall days.This research provides a basis for selecting climate change datasets and managing water resources in alpine regions. 展开更多
关键词 Multi-sources data Precipitation types Accuracy CTMR
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Metabolic mechanism of dietary factors and effect of dietary types associated with hyperuricemia:a review
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作者 Kaina Qiao Xuewei Zhou +3 位作者 Lili Zhang Wangang Zhang Baoguo Sun Yuyu Zhang 《Food Science and Human Wellness》 2025年第3期835-849,共15页
Globally,hyperuricemia is a growing health,social,and economic problem which could cause gout,chronic kidney diseases and other diseases.There are increasing evidences that a sensible diet makes sense to reduce the ri... Globally,hyperuricemia is a growing health,social,and economic problem which could cause gout,chronic kidney diseases and other diseases.There are increasing evidences that a sensible diet makes sense to reduce the risk of hyperuricemia.This review aims to explore the metabolic mechanism of dietary factors and effects of dietary types associated with hyperuricemia.Recommendations for dietary modification to prevent hyperuricemia are as following:decreasing intake of animal organs,seafood,sugar-sweetened,and alcohol beverages is essential;choosing water or unsweetened tea and coffee instead of sweetened beverages is beneficial;and increasing intake of vegetables,reduced-fat dairy products,foods containing fiber,micronutrients and unsaturated fatty acids is helpful.In addition,consumption of fruits and legumes in moderation is advantageous,and low-fructose of fruits and low-purine of non-soy beans are recommended.Moreover,personalized diet needs to be emphasized for hyperuricemic patients accompanied with diverse metabolic diseases. 展开更多
关键词 PURINE Metabolic mechanism Dietary types HYPERURICEMIA Personalized diet
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Sources and types of collagens used in the cosmetic industry
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作者 Mingjie Tong Xiaona Zhang +2 位作者 Jiongni Zhong Qiuling Xie Sheng Xiong 《Journal of Dermatologic Science and Cosmetic Technology》 2025年第1期64-72,共9页
Collagen is a class of mammalian extracellular matrix of the main structural proteins,widely present in the skin,bone,muscle and other tissues and it plays a role in supporting,repairing,and protecting tissue cells.Na... Collagen is a class of mammalian extracellular matrix of the main structural proteins,widely present in the skin,bone,muscle and other tissues and it plays a role in supporting,repairing,and protecting tissue cells.Natural source extraction and artificial synthesis provide a rich source of collagen.As a macromolecular material,collagen has good application potential in cosmetics,pharmaceutical,medical and food industries.Collagen has generated a great deal of interest in the cosmetic industry due to its abundance,strength,and direct correlation with skin aging.Collagen is widely used in cosmetics due to its unique structure,good biocompatibility and low antigenicity,as well as rich biological functions.To enhance the youthfulness and health of the user,the cosmetic industry adds collagen to products such as eye creams,face creams,and nutritional supplements,and uses it in medical aesthetic techniques such as tissue fillers,skin replacement,and soft skin enhancement.This paper mainly reviews the sources and types of collagen used in cosmetics industry,then introduces the effects of collagen in cosmetics and prospects the development prospects of collagen in dermatologic and cosmetic fields. 展开更多
关键词 Collagen Sources and types Cosmetic industry COSMETICS
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A new approach for identifying dominant cloud types and relationships between cloud types and precipitation vertical structure in tropical regions
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作者 Yuhao Lin Chunsong Lu +1 位作者 Yunying Li Ru Zhou 《Atmospheric and Oceanic Science Letters》 2025年第6期15-21,共7页
Cloud type profoundly affects precipitation,but few studies have explored its impact on precipitation scale height.The authors calculated the ratio of the volume of each cloud type to the total cloud volume and partit... Cloud type profoundly affects precipitation,but few studies have explored its impact on precipitation scale height.The authors calculated the ratio of the volume of each cloud type to the total cloud volume and partitioned the tropical region based on the dominant cloud types.Based on this,tropical regions were categorized into altocumulus control regions,stratocumulus control regions,deep convective cloud control regions,and transition regions.These regions exhibit unique characteristics:high precipitation scale heights and low surface precipitation rates in altocumulus control regions;low precipitation scale heights and low surface precipitation rates in stratocumulus control regions;and moderate precipitation scale heights with high surface precipitation rates in deep convective cloud regions.These features arise from differences in cloud characteristics,precipitation probability,and intensity,influenced by varying water vapor structures.In terms of physical mechanisms,altocumulus,stratocumulus,and deep convective cloud regions are characterized by total dryness,upper-level dryness with lower-level wetness,and total wetness,respectively.Upper-layer dryness leads to low cloud and precipitation structures,reducing the precipitation scale height,while lower-layer dryness increases it.Different humidity conditions in the upper and lower layers lead to variations in cloud type and volume distribution,ultimately affecting precipitation scale heights.This finding aids the mechanistic study of cloud precipitation physics in the tropics,providing valuable insights for developing numerical models and parameterizations. 展开更多
关键词 Precipitation scale height Cloud types PRECIPITATION TROPICS TRMM CloudSat-CALIPSO
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Tree diversity drives understory carbon storage rather than overstory carbon storage across forest types
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作者 Saif Ullah Jianping Wu +6 位作者 Jawad Ali Shah Xuemei Wang Yueming Lyu Zhiwen Guo Kashif Ali Deyun Chen Han Sun 《Journal of Forestry Research》 2025年第1期87-101,共15页
Although numerous studies have proposed explanations for the specific and relative effects of stand structure,plant diversity,and environmental conditions on carbon(C)storage in forest ecosystems,understanding how the... Although numerous studies have proposed explanations for the specific and relative effects of stand structure,plant diversity,and environmental conditions on carbon(C)storage in forest ecosystems,understanding how these factors collectively affect C storage in different community layers(trees,shrubs,and herbs)and forest types(mixed,broad-leaved(E),broad-leaved(M),and coniferous forest)continues to pose challenges.To address this,we used structural equation models to quantify the influence of biotic factors(mean DBH,mean height,maximum height,stem density,and basal area)and abiotic factors(elevation and canopy openness),as well as metrics of species diversity(Shannon–Wiener index,Simpson index,and Pielou’s evenness)in various forest types.Our analysis revealed the critical roles of forest types and elevation in explaining a substantial portion of variability in C storage in the overstory layer,with a moderate influence of stand factors(mean DBH and basal area)and a slightly negative impact of tree species diversity(Shannon–Wiener index).Notably,forest height emerged as the primary predictor of C storage in the herb layer.Regression relationships further highlighted the significant contribution of tree species diversity to mean height,understory C storage,and branch biomass within the forest ecosystem.Our insights into tree species diversity,derived from structural equation modeling of C storage in the overstory,suggest that the effects of tree species diversity may be influenced by stem biomass in statistical reasoning within temperate forests.Further research should also integrate tree species diversity with tree components biomass,forest mean height,understory C,and canopy openness to understand complex relationships and maintain healthy and sustainable ecosystems in the face of global climate challenges. 展开更多
关键词 Forest types Forest height Stand factors ELEVATION Forest strata
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Net energy of grains for dairy goats differed with processing methods and grain types
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作者 Xiaodong Su Lei Zhang +8 位作者 Yiyang Sun Yanbo Wu Jianrong Ren Shengru Wu Xinjian Lei Jun Zhang Dangdang Wang Hao Ren Junhu Yao 《Journal of Animal Science and Biotechnology》 2025年第2期729-740,共12页
Background The diverse types and processing methods of grains intricately influence the sites and digestibility of starch digestion,thereby impacting energy utilization.This study aimed to explore the impact of grain ... Background The diverse types and processing methods of grains intricately influence the sites and digestibility of starch digestion,thereby impacting energy utilization.This study aimed to explore the impact of grain variety and processing methods on the net energy(NE)in dairy goats,analyzing these effects at the level of nutrient digestion and metabolism.Methods Eighteen castrated Guanzhong dairy goats(44.25±3.59 kg BW)were randomly divided into 3 groups,each consisting of 6 replicates.The substitution method was employed to determine the NE values of the dry-rolled corn(DRC),dry-rolled wheat(DRW)or steam-flaked corn(SFC,360 g/L).Briefly,two phases were performed.Throughout the basal phase,all goats were fed the same basal diet.In the substitution phase,30%of the basal diet was replaced with DRC,DRW and SFC,respectively.Results In this study,the NE values of the DRC,DRW and SFC were 7.65,7.54 and 7.44 MJ/kg DM,respectively.Compared to the DRC group,the DRW group showed increased digestibility of starch and crude protein(CP).Similarly,the SFC group exhibited increased organic matter(OM)and starch digestibility and a trend towards higher dry matter(DM)digestibility,reduced fecal OM and starch content.Additionally,fecal volatile fatty acid(VFA)concentrations decreased in goats fed SFC.Correspondingly,digestible energy(DE)in the DRW and SFC groups tended to be higher than in the DRC group.DRW increased total VFA concentration compared to DRC,while SFC increased the proportion of propionate and decreased the acetate-to-propionate ratio in the rumen.Both the DRW and SFC diets elevated serum glucose levels.Furthermore,heat increment(HI)and gaseous energy(Gas E)related to fermentation were significantly higher in the DRW and SFC groups compared to the DRC group.Conclusion Our findings indicated that DRW and SFC increased rumen starch fermentation in goats,thereby improving total tract starch digestion and DE.However,DRW and SFC failed to improve NE value due to increased heat and gas energy production from fermentation.Therefore,excessively refined grains processing in the diet of dairy goats does not effectively improve energy efficiency. 展开更多
关键词 Dairy goats Energy metabolism Grain types PROCESSING Starch digestion
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Correlation of pathological types and imaging features in pancreatic cancer
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作者 Qiu-Long Wang Xiao-Jun Yang 《World Journal of Gastrointestinal Oncology》 2025年第8期420-424,共5页
The study by Luo et al published in the World Journal of Gastrointestinal Oncology presents a thorough and scientific methodology.Pancreatic cancer is the most challenging malignancy in the digestive system,exhibiting... The study by Luo et al published in the World Journal of Gastrointestinal Oncology presents a thorough and scientific methodology.Pancreatic cancer is the most challenging malignancy in the digestive system,exhibiting one of the highest mortality rates associated with cancer globally.The delayed onset of symptoms and diagnosis often results in metastasis or local progression of the cancer,thereby constraining treatment options and outcomes.For these patients,prompt tumour identification and treatment strategising are crucial.The present objective of pancreatic cancer research is to examine the correlation between various pathological types and imaging data to facilitate therapeutic decision-making.This study aims to clarify the correlation between diverse pathological markers and imaging in pancreatic cancer patients,with prospective longitudinal studies potentially providing novel insights into the diagnosis and treatment of pancreatic cancer. 展开更多
关键词 Pancreatic cancer Pathological types Imaging features ASSOCIATION Noninvasive tests
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The association of isocarbophos and isofenphos with different types of glucose metabolism:The role of inflammatory cells
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作者 Jintian Geng Dandan Wei +9 位作者 Lulu Wang Qingqing Xu Juan Wang Jiayu Shi Cuicui Ma Mengzhen Zhao Wenqian Huo Tao Jing Chongjian Wang Zhenxing Mao 《Journal of Environmental Sciences》 2025年第1期322-331,共10页
To investigate the associations between isocarbophos and isofenphos with impaired fasting glucose(IFG)and type 2 diabetes mellitus(T2DM),and to assess the mediation roles of inflammation cells.There were 2701 particip... To investigate the associations between isocarbophos and isofenphos with impaired fasting glucose(IFG)and type 2 diabetes mellitus(T2DM),and to assess the mediation roles of inflammation cells.There were 2701 participants in the case-control study,including 896 patients with T2DM,900 patients with IFG,905 subjects with NGT.Plasma isocarbophos and isofenphos concentrationsweremeasured using gas chromatography and triple quadrupole tandem mass spectrometry.Generalized linear models were used to calculate the relationships between plasma isofenphos and isocarbophos levels with inflammatory factor levels and T2DM.Inflammatory cell was used as mediators to estimate the mediating effects on the above associations.Isocarbophos and isofenphos were positively related with T2DM after adjusting for other factors.The odds ratio(95%confidence interval)(OR(95%CI))for T2DM was 1.041(1.015,1.068)and for IFG was 1.066(1.009,1.127)per unit rise in ln-isocarbophos.The prevalence of T2DM increased by 6.4%for every 1 unit more of ln-isofenphos(OR(95%CI):1.064(1.041,1.087)).Additionally,a 100%rise in ln-isocarbophos was linked to 3.3%higher ln-HOMA2IR and a 0.029 mmol/L higher glycosylated hemoglobin(HbA1c)(95%CI:0.007,0.051).While a 100%rise in ln-isofenphos was linked to increase in ln-HOMA2 and ln-HOMA2IR of 5.8%and 3.4%,respectively.Furthermore,white blood cell(WBC)and neutrophilic(NE)were found to be mediators in the relationship between isocarbophos and T2DM,and the corresponding proportions were 17.12%and 17.67%,respectively.Isofenphos and isocarbophos are associated with IFG and T2DM in the rural Chinese population,WBC and NE have a significant role in this relationship. 展开更多
关键词 ISOCARBOPHOS Isofenphos type 2 diabetes mellitus Inflammatory cells Mediation effect
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Exploring the Effectiveness of a Rapid Diagnostic Kit for Identifying Snake Venom Types in Blood Tests
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作者 Linfeng Zheng Ming Liu +1 位作者 Ying Gao Biao Wu 《Journal of Clinical and Nursing Research》 2025年第4期110-115,共6页
Objective:To develop a rapid diagnostic kit for identifying snake venom types,aimed at providing a basis for clinical diagnosis and laying a foundation for early treatment through quick blood testing of injured patien... Objective:To develop a rapid diagnostic kit for identifying snake venom types,aimed at providing a basis for clinical diagnosis and laying a foundation for early treatment through quick blood testing of injured patients.Methods:Anti-snake venom immunoglobulin(IgG)was prepared,biotinylated specific IgG was screened,detection enzyme-labeled strips were produced,and rapid identification of snakebites was performed.Pre-experimental verification was conducted to establish standard curves and confirm specificity.The kit was tested on clinical samples and the results were analyzed.Repeatability and stability were evaluated through multiple repeated tests and experiments under different storage conditions.Finally,sensitivity and specificity were calculated,receiver operating characteristic curves(ROC curves)were drawn,and statistical analysis software was used for data analysis to ensure the reliability and effectiveness of the kit.Results:The test showed high sensitivity and specificity.Conclusion:The rapid diagnostic kit for identifying snake venom types in blood tests demonstrates high reliability and effectiveness in clinical diagnosis. 展开更多
关键词 Blood test Snake venom types Rapid diagnostic kit
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Urban vegetation types and bryophyte diversity:why woodlands matter
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作者 Zhijie Zhou Ping Fang +4 位作者 Lei Dong Zhenkai Sun Qin Zuo Jianan Wang Dexian Zhao 《Journal of Forestry Research》 2025年第5期190-201,共12页
Various types of vegetative cover,predominantly woodlands,shrublands,and grasslands,provide a range of habitats for urban organisms and are the main contributors to urban ecosystem services.The goal of this study was ... Various types of vegetative cover,predominantly woodlands,shrublands,and grasslands,provide a range of habitats for urban organisms and are the main contributors to urban ecosystem services.The goal of this study was to assess the potential of different vegetation types in maintaining and enhancing bryophyte diversity in urban areas.Bryophytes,small non-vascular plants,in woodlands,shrublands,and grasslands in Hefei city(eastern China)were investigated,and their species richness,abundance,community composition and relationships with habitat characteristics were analysed.The results show that urban woodlands had the highest species richness and abundance of bryophytes and a distinct community composition compared with the other vegetation types.Relative light intensity had a positive effect on species richness in urban woodlands,whereas litter cover had a negative effect on abundance.Shrub,grass and litter covers,and relative air humidity were the main factors driving the differences in bryophyte species composition between woodlands and other vegetation types.Therefore,owing to their high potential to maintain bryophyte diversity,woodlands should receive increased attention during the construction of urban green spaces.In addition,promoting structural heterogeneity and increasing light availability would be beneficial to bryophyte species diversity. 展开更多
关键词 Urban green spaces Vegetation types CRYPTOGAMS Biodiversity conservation Habitat heterogeneity
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